U.S. patent application number 10/901896 was filed with the patent office on 2005-03-10 for rotating soft tissue biopsy needle.
Invention is credited to Goldenberg, Alec S..
Application Number | 20050054947 10/901896 |
Document ID | / |
Family ID | 34228623 |
Filed Date | 2005-03-10 |
United States Patent
Application |
20050054947 |
Kind Code |
A1 |
Goldenberg, Alec S. |
March 10, 2005 |
Rotating soft tissue biopsy needle
Abstract
In one embodiment, a biopsy needle that is particularly suited
for shearing and collecting soft tissue specimens is provided and
is formed of an inner tube with a snare at a distal end thereof, an
outer cannula, a stylet and a handle assembly. In one aspect of the
present invention, the handle assembly includes a spring loaded
mechanism described in greater detail below that permits the user
to selectively actuate the biopsy needle so that the outer cannula
and the inner tube are rapidly advanced beyond the stylet to
provide a shearing action of the soft tissue specimen. In one
exemplary embodiment, the rapid advancement of the needle to
achieve appropriate shear/cutting forces and to facilitate specimen
transit into the needle is accomplished by a first spring loaded
mechanism. A second spring loaded mechanism is automatically
actuated after actuation of the first spring loaded mechanism and
serves to rotate the inner tube relative to the outer cannula
resulting in actuation of the snare coil.
Inventors: |
Goldenberg, Alec S.; (New
York, NY) |
Correspondence
Address: |
DARBY & DARBY P.C.
P. O. BOX 5257
NEW YORK
NY
10150-5257
US
|
Family ID: |
34228623 |
Appl. No.: |
10/901896 |
Filed: |
July 29, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60498417 |
Aug 28, 2003 |
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Current U.S.
Class: |
600/567 |
Current CPC
Class: |
A61B 10/0275 20130101;
A61B 10/0266 20130101; A61B 10/04 20130101; A61B 10/0233 20130101;
A61B 2010/0208 20130101; A61B 17/32002 20130101 |
Class at
Publication: |
600/567 |
International
Class: |
A61B 010/00 |
Claims
What is claimed is:
1. A biopsy needle for collecting a tissue specimen, the needle
including a cannula having a first profile feature, a stylet and a
handle assembly that includes a biased mechanism that permits a
user to selectively actuate the biopsy needle so that the cannula
rapidly advances beyond the stylet to provide a shearing action of
the tissue specimen as the cannula is simultaneously rotated due to
interaction between the first profile feature and the biased
mechanism so as to generate a rotational coring action.
2. The needle of claim 1, wherein the first profile feature
comprises one of a pin and a slot.
3. A biopsy needle for collecting a tissue specimen, the needle
including at least an inner tube and a handle assembly that
includes a torque generating mechanism that imparts a selective and
controlled torque action to the inner tube relative to the handle
assembly as the inner tube is advanced forward, the torque
generating mechanism including a first component that is coupled to
and associated with the inner tube and a second component that is a
part of a housing of the handle assembly.
4. The needle of claim 3, further including a stylet that is
slidably disposed within the inner tube and an outer tube that is
disposed about the inner tube, the inner and outer tubes being
coupled to one another.
5. The needle of claim 3, wherein one of the first and second
components is permitted to move axially, while the other of the
first and second components is fixed in an axial direction.
6. The needle of claim 4, wherein the first component is a helical
slot formed in the inner tube and the second component is a pin
that is fixed to the handle assembly and is received in the helical
slot and the needle further includes a first biasing mechanism that
permits a user to selectively actuate the biopsy needle so that the
inner tube and outer cannula are rapidly advanced beyond the stylet
to provide a shearing action of the tissue specimen.
7. The needle of claim 4, wherein the first component is a pin that
travels axially as the inner tube moves axially and the second
component is a helical slot that is formed in a housing of the
handle assembly, with the pin being received in the helical slot,
such that when the inner tube travels axially, the pin travels
within the helical slot, thereby causing rotation of the inner tube
relative to the handle assembly.
8. The needle of claim 4, wherein the first component is a helical
slot formed in the inner tube and is fixed in an axial direction,
while the second component is a pin that is part of a housing of
the handle assembly and is received in the helical slot and moves
axially therein, thereby causing the inner tube to rotate relative
to the handle assembly.
9. The needle of claim 4, wherein the first component is a pin that
is axially fixed and the second component is a helical slot formed
in a housing of the handle assembly, the slot receiving the pin and
moving axially relative to the handle assembly, thereby causing the
inner tube to rotate relative to the handle assembly.
10. The needle of claim 4, wherein the needle is of a snare coil
type and includes a snare coil that is operatively connected to the
inner tube such that when the inner tube rotates, the snare coil at
least partially winds down.
11. A biopsy needle for collecting a tissue specimen, the needle
including an inner tube with a snare coil at a distal end thereof,
an outer cannula, a stylet and a handle assembly that includes a
first torque generating mechanism that imparts a selective and
controlled torque action to the outer cannula relative to the
handle assembly to cause actuation of a second torque generating
mechanism that imparts a selective and controlled torque action to
the inner tube relative to the outer cannula as the inner tube and
outer cannula are advanced forward resulting in the snare coil at
least partially closing, the first torque generating mechanism
including a first component that is coupled to and associated with
the outer cannula and a second component that is a part of a
housing of the handle assembly, the needle further including an
alignment sleeve that is disposed around a portion of the inner
tube and the outer cannula, the alignment sleeve being received
with a complementary groove formed in the housing so as to permit
rotation of the alignment sleeve but restrict axial movement
thereof, the alignment sleeve having guide channels formed therein
to receive and control movement of the inner tube relative to the
outer cannula such that in a first stage, both the inner tube and
outer cannula move axially within the guide channels, while being
prevented from rotating relative to one another and in a second
stage, the inner tube is permitted to rotate relative to the outer
cannula to cause actuation of the snare coil.
12. The needle of claim 11, wherein the second stage occurs after
the inner tube and outer cannula are axially advanced, during the
first stage, to a predetermined position where the outer cannula
clears and becomes free of the guide channels of the alignment
sleeve, whereby the outer cannula rotates relative to the
innertube.
13. The needle of claim 11, wherein the alignment sleeve contains a
pair of guide channels formed about 180 degrees apart from one
another, each groove extending the entire length of an inner
surface of the alignment sleeve.
14. The needle of claim 12, wherein the outer cannula has a first
flange formed as a part thereof, the first flange including a pair
of first tabs and the inner tube has a second flange formed as a
part thereof, the second flange including a pair of second tabs,
one pair of first and second tabs being disposed in one guide
channel, while a second pair of first and second tabs being
disposed in the other guide channel, each of the first and second
flanges having a locking lip that face one another for detachably
locking the inner tube and the outer cannula to one another in the
first stage.
15. The needle of claim 14, wherein the locking lips of the first
and second flanges permit uniform rotation of the inner tube and
the outer cannula such that the outer cannula and the inner tube
remain in a locked position until the outer cannula becomes
disengaged from the alignment sleeve and begins to rotate relative
to the inner tube at which time the locking lip associated with the
first flange becomes free and unlocked from the other locking lip
of the second flange.
16. The needle of claim 11, wherein the first component comprises a
first helical slot formed in the outer cannula and the second
component comprises a first pin that is received in the first
helical slot and is fixed to the housing of the handle assembly
such that axial movement of the outer cannula in the first stage is
translated to rotational movement thereof due to the first pin the
first helical slot, whereby rotation of the outer cannula is
translated to rotation of the alignment sleeve and the inner tube
due to the outer cannula being coupled to both.
17. The needle of claim 11, wherein the first component comprises a
first pin formed as part of the outer cannula and the second
component comprises a first helical slot formed in the housing of
the handle assembly, that receives the first pin, such that axial
movement of the outer cannula in the first stage is translated to
rotational movement thereof due to the first pin traveling in the
first helical slot, whereby rotation of the outer cannula is
translated to rotation of the alignment sleeve and the inner tube
due to the outer cannula being coupled to both.
18. The needle of claim 11, wherein the second torque generating
mechanism is constructed to automatically actuate at a
predetermined point when the inner tube and outer cannula are
axially advancing after activation of the first torque generating
mechanism, the inner tube including one of a drive pin and a groove
and a housing of the handle assembly including the other of the
drive pin and groove such that as the inner tube and the outer
cannula axially moves, the drive pin travels within the groove that
is helically shaped so as to impart a rotation to the inner tube
relative to the outer cannula as the drive pin travels within the
helical groove.
19. The needle of claim 11, wherein the second torque generating
mechanism includes: a second pivoting member that is pivotably
coupled at a first end to a proximal end of the inner tube, with a
second end including a claw, the second pivoting member includes a
cam slot that receives a fixed pin that is fixed to the housing of
the handle assembly such that as the inner tube and outer cannula
move axially, the fixed pin travels within the cam surface causing
a lifting of the second end; a retainer ring disposed about the
inner tube and being engaged by the claw when the second biasing
mechanism is in an energy storing position; a second biasing
element disposed between the proximal end of the inner tube and the
retainer ring and in a compressed state in the energy storing
position; and wherein when the second torque generating mechanism
is activated, the claw lifts off the retainer ring, thereby
releasing the retainer ring and the second biasing element.
20. The needle of claim 19, wherein the drive pin contacts the
retainer ring such that release of the retainer ring drives the
drive pin within guide grooves that are formed in the handle
assembly and contain the drive pin in a single plane, the stylet
having an opening formed therethrough to accommodate the drive pin,
wherein planar advancement of the drive pin in the guide slots and
advancement of the drive pin in the helical groove is translated
into rotation of the inner tube relative to the outer cannula.
21. The needle of claim 12, wherein the predetermined position
occurs prior to the inner tube and the outer cannula reaching the
end of their axial travel such that rotation is imparted to the
inner tube as it axially advances.
22. The needle of claim 12, wherein the predetermined position
occurs after the inner tube and the outer cannula reach ends of
their axial travel.
23. The needle of claim 11, wherein the first torque generating
mechanism also acts to rapidly advance the inner tube and the outer
cannula beyond the stylet to provide a shearing action of the
tissue specimen as at least the outer cannula is simultaneously
rotated.
24. The needle of claim 23, wherein the inner tube and outer
cannula are advanced over and beyond the stylet during both the
first and second stages.
25. The needle of claim 11, wherein the first torque generating
mechanism includes a first actuator operatively coupled to pivoting
links that terminate in a claw at one end that engages a flange of
the inner tube in an energy storing position so as to restrict
axial movement of the inner tube and maintain the first biasing
element in a compressed state.
26. The needle of claim 1, wherein during a rapid advancement
stage, the inner tube and the outer cannula move in tandem and
substantially free of rotation relative to one another.
27. The needle of claim 1, further including: means for generating
negative pressure within the needle for causing the specimen to
more readily enter the needle, the means including a first seal and
a second seal, the first seal being disposed between the stylet and
the inner tube that generates a vacuum within a distal portion of
the needle during axial travel of the inner tube and the outer
cannula facilitating specimen transit into the needle, the second
seal being disposed between the outer cannula and the inner
tube.
28. The needle of claim 1, wherein the outer cannula has a first
window formed therein and the inner tube has a second window which
is selectively axially aligned with the first window when the inner
tube is rotated within the outer cannula to a position where the
windows at least partially overlap one another after the snare coil
is tightened to permit access to the specimen collected in the
needle.
29. A biopsy needle for collecting a tissue specimen, the needle
including an outer cannula, an inner tube received within the outer
cannula and a stylet that is received within the inner tube, the
inner tube having a snare coil at a distal end thereof, the outer
cannula and the inner tube being coupled to one another by a
linking feature that permits one of the outer cannula and inner
tube to rotate relative to the other, the needle having a first
actuation stage and a second actuation stage that is automatically
activated as a result of activation of the first actuation stage,
wherein during the first actuation stage, a first torque generating
mechanism is actuated to drive the outer cannula in an axial
longitudinal direction as well as causing rotation of the outer
cannula as it is driven, the needle further including an alignment
sleeve that is axially fixed but rotatable and constructed to
receive both the outer cannula and the inner tube such that the
outer cannula and inner tube can freely travel axially within the
alignment sleeve, wherein in the first stage, rotation of the outer
cannula is translated to rotation of the alignment sleeve, and
wherein in the second stage, the outer cannula is free of the
alignment sleeve and the inner tube is rotated, as it remains
axially steadfast, due to activation of a second biasing mechanism,
whereby rotation of the inner tube is translated into rotation of
the alignment sleeve and any rotation of the outer cannula is at a
speed less than a speed of the inner tube such that the relative
rotation between the outer cannula and the inner tube causes
activation of the snare coil.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. patent
application Ser. No. 60/498,417, filed Aug. 28, 2003, which is
hereby incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to a surgical instrument,
typically known as a biopsy needle or cannula that is used to
gather tissue from living persons or animals for pathological study
and more particularly, relates to a rotating biopsy needle having
an improved structure for severing a soft tissue sample and/or
retaining the tissue sample within the biopsy needle.
BACKGROUND
[0003] For various medical reasons, such as diagnostic tests or the
like, it is often necessary for a physician to obtain a sample of a
patient's body. Often, it is required for the physician to take a
sample from a soft tissue such as a breast biopsy specimen as
opposed to a more rigid structure, such as a bone marrow specimen.
Soft tissue specimens generally contain a less rigid structure and
are by definition "soft" or easily deformable as opposed to bone
marrow structures which are recovered with significant portions of
their internal bony trabecular structure intact.
[0004] One exemplary surgical instrument for the severing and/or
retrieval of biopsy specimens is disclosed in U.S. Pat. Nos.
5,522,398; 5843,001; and 6,015,391, of which the present applicant
is also inventor. Each of these patents is hereby expressly
incorporated herein by reference. While these instruments are
particularly suited for severing and collecting a more rigid tissue
specimen, such as a bone marrow specimen, the instruments are not
as effective at severing and/or retaining soft tissue samples. In
addition, the concept of recovering a specimen by pushing it toward
the handle from the tip of the needle may not be as applicable for
soft tissue specimens as it is for bone marrow specimens. An
attempt to push the specimen through the needle can result in
disruption of the specimen because soft tissue specimens have less
structure. Moreover in a long needle, such as an endoscopic
SNARECOIL (trademark) needle, the length of the needle would be
prohibitive in successfully pushing the specimen out of the
proximal end of the needle and recovering an intact sample.
[0005] Other conventional procedures and instruments used for
obtaining the samples, while not overly complex, almost universally
result in excessive patient discomfort and often overly extends the
patient's and operator's time and money.
SUMMARY
[0006] In one embodiment, a biopsy needle that is particularly
suited for shearing and collecting soft tissue specimens is
provided and is formed of an inner tube with a snare at a distal
end thereof, an outer cannula, a stylet and a handle assembly. In
one aspect of the present invention, the handle assembly includes a
first biasing mechanism described in greater detail below that
permits the user to selectively actuate the biopsy needle so that
the outer cannula and the inner tube are rapidly advanced beyond
the stylet to provide a shearing action of the soft tissue
specimen. The biopsy needle also includes a second biasing
mechanism that automatically actuates subsequent to the actuation
of the first biasing mechanism and serves to rotate the inner tube
relative to the outer cannula to actuate the snare coil in a staged
manner. In other words, the needle is of a rotating type in that in
one embodiment, a cannula (outer cannula) is connected to a sleeve
with a pin and groove mechanism that causes it to rotate as it is
rapidly advanced.
[0007] In another aspect of the present invention, a three cannula
needle is provided and includes a third retractable cannula that
can be selectively retracted over the outer cannula so as to expose
a specimen that is sitting in the innermost member, namely, the
inner tube. More specifically, each of the inner tube and the outer
cannula has a cut away portion (window) that are both in
registration with one another after the outer cannula and inner
tube have been axially projected and rotated to an end position
where the specimen has been sheared and captured within the inner
tube. To expose the aligned windows, the third outer most
retractable cannula is simply moved back and the user can easily
recover the specimen that is resting within the cradle of the inner
tube. This facilitates removal of the specimen.
[0008] Other features and advantages of the present invention will
be apparent from the following detailed description when read in
conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0009] The foregoing and other features of the present invention
will be more readily apparent from the following detailed
description and drawings figures of illustrative embodiments of the
invention in which:
[0010] FIG. 1 is a perspective view of a biopsy needle according to
a first embodiment;
[0011] FIG. 2 is an exploded perspective view of the needle of FIG.
1;
[0012] FIG. 3 is an exploded perspective view, in partial
cross-section, of a rotating sleeve that is disposed about a length
of an outer cannula of the needle;
[0013] FIG. 4 is an exploded perspective view, in partial
cross-section, of an alignment sleeve of the needle of FIG. 1;
[0014] FIG. 5 is a cross-sectional view taken along the line 5-5 of
FIG. 4;
[0015] FIG. 6 is a cross-sectional elevation view of the needle of
FIG. 1 in a rest position;
[0016] FIG. 7 is a cross-sectional elevation view of the needle of
FIG. 1 at an intermediate position of a first stage;
[0017] FIG. 8 is a cross-sectional elevation view of the needle of
FIG. 1 shown at the completion of the first stage;
[0018] FIG. 9 is a cross-sectional elevation view of the needle of
FIG. 1 shown at the completion of a second stage;
[0019] FIG. 10 is an enlarged sectional view taken around the
circle of FIG. 8;
[0020] FIG. 11 is an enlarged sectional view taken around the
circle of FIG. 9;
[0021] FIG. 12 is a partial perspective view of a biopsy needle
having an internal window according to a first embodiment; and
[0022] FIG. 13 is a partial perspective view of a biopsy needle
having an internal window according to a second embodiment.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0023] Referring now to FIGS. 1-11, a biopsy needle 100 according
to one exemplary embodiment is illustrated. The biopsy needle 100
includes an inner tube 110 with a snare 300 at a distal end
thereof, an outer cannula 120, a stylet 310 and a handle assembly
400. In one aspect of the present invention, the handle assembly
400 includes a biasing (spring loaded) mechanism described in
greater detail below that permits the user to selectively actuate
the biopsy needle 100 so that the outer cannula 120 and the inner
tube 110 are rapidly advanced beyond the stylet 310 to provide a
shearing action of the soft tissue specimen.
[0024] The present biopsy needle 100 is constructed for soft biopsy
applications since the spring loaded mechanism provides an improved
means of removing the tissue after it is cored as well as providing
an improvement in the way that the tissue is acquired by the needle
100. The handle assembly 400 includes a handle body 410 that can be
formed in number of different shapes and sizes and is generally a
hollow body that contains the spring loaded mechanism. For purpose
of illustration only, the handle body 410 of FIG. 1 is a generally
rectangular or square body; however, handle body 410 preferably is
an ergonomically pleasing shape. The handle body 410 includes an
opening 412 that permits a portion of a first mechanical mechanism
to extend therethrough so as to be accessible by the user as is
described in greater detail below.
[0025] The inner tube 110 is preferably similar or identical to the
inner tube disclosed in one of the aforementioned patents. More
specifically, the inner tube 110 includes a distal end and an
opposing proximal end 114. The inner tube 110 can have any number
of different cross-sectional shapes; however, in one embodiment,
the inner tube 110 has a circular cross-section. The inner tube 110
includes a flange 116 that is spaced from the proximal end 114 and
extends outwardly from the inner tube 110. The flange 116 can be in
the form of an annular flange that extends completely around the
inner tube 110 or it can be in the form of one or more protrusions,
e.g., tabs, that extend outward from the inner tube 110. In the
illustrated embodiment, the flange 116 is in the form of an annular
ring with a pair of integral tabs (ears) 117 formed as part of the
flange 116 and extending outwardly therefrom. The pair of tabs 117
are spaced apart from one another and preferably, the tabs 117 are
spaced about 180 degrees apart from one another and the outer
sections of the tabs 117 have curved surfaces.
[0026] The outer cannula 120 is preferably similar or identical to
the outer tube disclosed in one of the aforementioned patents. More
specifically, the outer cannula 120 includes a distal end and an
opposing proximal end 124. The outer cannula 120 can also have any
number of different cross-sectional shapes with one embodiment
being a circular tube structure. At the proximal end 124 of the
outer cannula 120, a flange 126 is formed. As with the flange 116,
the flange 126 can be in the form of an annular flange or it can be
formed by one or more protrusions or tabs. The outer cannula 120
also has a pair of tabs or ears 128 formed as a part thereof. As
with the inner tube 110, the pair of tabs 128 are spaced apart from
one another and preferably, the pair of tabs 128 are spaced apart
about 180 degrees.
[0027] Before proceeding to an explanation of the other operable
components of the spring loaded mechanism, it is helpful to
understand that generally the inner tube 110 and outer cannula 120
are positionable between two positions, namely, a fully retracted
position and a fully extended position. In the fully retracted
position, the inner tube 110 and outer cannula 120 are reset back
into the handle body 410 and a biasing element(s) of the spring
loaded mechanism stores energy. In contrast, after the user
activates the spring loaded mechanism, the biasing element releases
its energy and an axial force is applied to the inner and outer
tube structure in a direction away from the handle body 410.
[0028] In both the fully retracted and fully extended positions,
the flange members 116, 126 are coupled to one another, as
described below, so that a force applied to one of the inner tube
110 and the outer cannula 120 is translated to the other of the
inner tube 110 and outer cannula 120.
[0029] In order to generate a force that is sufficient to shear the
soft tissue, the spring loaded mechanism includes a first biasing
element 130, such as a coil spring, that applies a force against a
face of an outer sleeve 119 that is disposed around and connected
to the outer cannula 120 as shown in FIG. 3. More specifically, the
outer sleeve 119 has a first end at which a flange member 121 is
formed and a body section 122 which in the illustrated embodiment
is a tubular structure. The outer sleeve 119 is directly attached
to the outer cannula 120 so that movement of one of the members is
directly translated to the same type of movement of the other of
the members. The outer sleeve 119 has a groove 123 formed therein
and in one embodiment, the groove 123 has a spiral or helical
shape. The sleeve 119 can have two grooves and as used herein, the
term groove refers to either a recessed channel formed in a body or
a slot or opening that is formed completely through the body. In
addition, one will appreciate that other pin and groove
arrangements can be provided as a means for rotating the outer
cannula 120. For example, other designs are possible including
symmetrical placement of pins on both sides of the sleeve which
engage complementary grooves in the sleeve and can lead to a more
efficient and stable translation of the axial motion into a
rotation of the cannula. In addition, it will be appreciated that
the groove 123 can be formed in the outer cannula 120 itself, thus
eliminating the need for the sleeve 119.
[0030] One or more pins or projections 127 are received within the
groove 123 with the pin 127 being fixed relative to the handle body
410. More specifically, each pin 127 is securely attached to the
handle body 410 and is sized so that it at least partially extends
into the groove 123. In other words, it is sufficient for the pin
127 to be a small projection coupled to housing 410 which extends
into the groove 123. One will appreciate that this is a pin in
groove arrangement and therefore, when the outer cannula/outer
sleeve is advanced, the pin 127 travels within the groove 123 and
the helical nature of the groove 123 causes the outer cannula/outer
sleeve to rotate as the outer cannula 120 continues to advance
axially in the longitudinal direction.
[0031] The first biasing element 130 is contained within the handle
body 410 by being disposed between the flange 121 and an
interference member 140 that is formed as part of the handle body
410 such that the outer cannula 120 can freely travel therethrough
in a sliding manner, while the first biasing element 130 is
external to the outer cannula 120. More specifically, the
interference member 140 can be in the form of an annular flange
that has an opening formed therethrough to accommodate the outer
cannula 120. The interference member 140 is thus fixed relative to
the handle 400 and relative to the movable inner tube 110 and outer
cannula 120.
[0032] The spring loaded mechanism includes an operable actuator
device 150 that causes the release of the first biasing element 130
from its compressed state, thereby resulting in the first biasing
element 130 releasing at least some of its stored energy. One
exemplary actuator device 150 is a pivotable lever that at least
partially extends through an opening 413 formed in the handle body
410. The device 150 has a button or the like 152 which the user
manipulates to cause the pivoting of the device 150 and release of
the first biasing element 130. The button 152 is disposed along an
outer surface of the handle body 410. The device 150 is formed of
an elongated finger or post 154 that has the button 152 attached or
formed at one end and terminates at the other end in a claw or tab
15 that is provided to engage the annular flange 116 and lock the
inner and outer tubes 110, 120 in the retracted position. The
device 150 includes a biasing element, such as a spring, 158 that
is attached at one end to the housing and at its other end to the
post 154 which applies a biasing force to the post 154, thereby
biasing the post 154 in a manner such that it engages and applies a
force against the flange 116 when the device 150 is in a closed
position. As the user slides the button 152, the biasing force of
the spring 158 is overcome and the device 150 pivots about the post
154 in a direction where the claw 156 clears the flange 116,
thereby releasing the inner tube 110 for axial movement.
[0033] As previously mentioned, the first biasing element 130
applies a biasing force against one face of the flange member 121
and since the outer sleeve 119 is directly connected to the outer
cannula 120, the first biasing element 130 likewise applies a force
to the outer cannula 120. When the claw 156 seats against the
flange 121 it acts to lock the outer sleeve/outer cannula in the
retracted position since it prevents any axial movement of the
outer cannula 120 or sleeve 119, which is frictional fit or
otherwise securely attached to the outer cannula 120, in a
direction away from the handle body 410.
[0034] As soon as the claw 156 becomes disengaged from the flange
116, the first biasing element 130 releases its stored energy by
applying a force against the flange 121. This release of energy
results in axial movement of the outer cannula 120 and sleeve 119
as sequentially shown in FIGS. 6-8. The sleeve 119 limits the
degree of travel of the outer cannula 120 since the sleeve 119 has
dimensions greater than the dimensions of the opening in the handle
body 410 through which the outer cannula 120 extends. In the fully
extended position, the sleeve 119 seats against the handle body 410
with the first biasing element 130 being in a more elongated
condition, released of its stored energy.
[0035] It will also be appreciated that an opposite arrangement
that achieves the same result can be provided, namely, one in which
the outer cannula 120 has one or more projections that travel in a
helical groove associated with the housing. Thus, after the flange
121 is disengages, the outer cannula 120 moves axially forward and
also begins to rotate since the pin or projections that are part of
the cannula 120 ride within the helical groove, so as to cause
rotation of the outer cannula as it is axially advanced.
[0036] The first stage which is defined by the release and axial
driving of the outer tube 120 can be characterized as being a
torque generating mechanism having a first component and a second
component with one component being fixed in the longitudinal axial
direction, while the other component is movable in the axial
direction. One of the components is associated with the outer
cannula, while the other component is associated with another part
of the needle. Thus, in one embodiment, the component associated
with the outer cannula moves axially and mates with the other
component which is fixed axially to cause rotation of the outer
cannula as it advances. In another embodiment, the components
associated with the outer cannula does not move axially and mates
with the other component that does move axially, thereby causing
rotation of the outer cannula 120 as it advances.
[0037] In the illustrated embodiment, as the outer sleeve 119 is
biased forward due to the first biasing element 130 releasing its
energy, the one or more fixed pins 127 control the manner in which
the outer sleeve 119 moves axially forward. More specifically, the
helical nature of the groove 123 causes the outer sleeve 119 to
begin to rotate as it is advanced axially forward. Since the outer
sleeve 119 is directly connected to the outer cannula 120, the
rotation of the outer sleeve 119 is directly translated into
rotation of the outer cannula 120.
[0038] Preferably, an alignment sleeve 160 is provided and is
disposed around a portion of the inner tube 110 and outer cannula
120. The alignment sleeve 160 is disclosed within the housing body
410 and is a generally hollow structure such that the outer cannula
120 and the inner tube 110 are received therethrough. In one
embodiment, the alignment sleeve 160 is a generally annular
structure with a flange 162 formed as part thereof and extending
outwardly from an outer surface 164 of the sleeve 160. The flange
162 is thus a radial flange that extends around the sleeve 160 and
serves to restrict the axial movement of the sleeve 160, while
permitting the sleeve 160 to rotate. More specifically, the flange
162 is received within a complementary groove or channel (not
shown) or other retaining structure which is formed in the body
410. By disposing the flange 162 in a complementary groove, the
alignment sleeve 160 is permitted to rotate therein; however, it
can not move axially forward in the housing.
[0039] The alignment sleeve 160 also has features formed within the
bore extending therethrough to locate and control the movement of
the inner tube 110 and the outer cannula 120. As best shown in
FIGS. 2 and 4, the alignment sleeve 160 has a pair of grooves or
channel 165 formed within an inside thereof. The grooves 165 are
constructed to receive the tabs 117, 128 of the flanges 116, 126 of
the inner tube 110 and the outer cannula 120, respectively, and
therefore, the grooves 165 are spaced apart from one another in the
same manner as the tabs 117, 128 of each of the inner tube 110 and
outer cannula 120 are spaced apart. In the illustrated embodiment,
the grooves 165 are thus spaced about 180 degrees apart from one
another. The grooves 165 have a complementary arcuate shape (e.g.,
semi-circular) so as to receive the tabs 117, 128 which themselves
are semi-circular. The grooves 165 extend from one end to the other
end of the alignment sleeve 160.
[0040] Since the grooves 165 have a complementary shape as the tabs
117, 128, the inner tube 110 and the outer cannula 120 are
permitted to move axially within the alignment sleeve 160; however,
the two are not permitted to rotate independent from one another.
Instead, the inner tube 110 and outer cannula 120 rotate together
when the alignment sleeve 160 itself rotates. As previously
mentioned, the alignment sleeve 160 does not move axially within
the handle body 410 but rather is only permitted to rotate and
thus, the rotation of the alignment sleeve 160 is directly
translated into rotation of the inner tube 110 and/or the outer
cannula 120.
[0041] FIG. 5 is an enlarged sectional view of the interaction and
coupling between the inner tube 110 and the outer cannula 120. More
specifically, the flange 126 at the proximal end of the outer
cannula 120 includes a first locking lip 127 and the flange 116 at
the proximal end of the inner tube 110 includes a second locking
lip 141 that is complementary to the first locking lip 127 such
that the two interlock with one another. The first locking lip 127
is formed on one face of the flange 126 and the second locking lip
141 is formed on the face of the flange 116 that faces the flange
126. The first locking lip 127 can be annular in shape or it can be
formed as one or more spaced lip segments so long as there are
complementary lip segments formed on the opposing second locking
lip 141. The first locking lip 127 has a portion 129 that is
perpendicular to the flange 126 such that it extends outwardly
therefrom and the portion 129 terminates in a lip portion 131. A
space 133 is formed between the lip portion 131 and the flange 126.
Similarly, the second locking lip 141 has a portion 143 that is
perpendicular to the flange 116 such that it extends outwardly
therefrom toward the flange 126 and the portion 143 terminates in a
lip portion 145. A space 147 is formed between the lip portion 145
and the flange 116. To couple the inner tube 110 to the outer
cannula 120, the lip portion 131 of the first locking lip 127 is
disposed within the space 147 and the lip portion 145 is received
within the space 133. In this manner, the lip portions 131, 145
interlock with one another and prevent independent axial movement
between the inner tube 110 and the outer cannula 120. FIG. 4 also
illustrates the tabs 117 of the flange 116 and the tabs 128 formed
as part of the flange 126.
[0042] It will be appreciated that the alignment sleeve 160 causes
the inner tube 110 to rotate since it is directly coupled to the
outer cannula 120 which can be set into rotation by actuation of
the device 150 as described hereinbefore. In other words, initial
rotation of the outer cannula is translated to rotation of the
sleeve 119 and the inner tube 110. More specifically, the pin and
groove construction of the sleeve 119 and the direct connection
between the sleeve 119 and the outer cannula 120 causes the
rotation of the outer cannula 120 upon actuation of the device 150
and because the inner tube 110 is captured within grooves 165 of
the alignment sleeve 160 as with the outer cannula 120, the
rotation of the outer cannula 120 is translated to rotation of the
alignment sleeve 160 which in turn translates rotation to the inner
tube 110. It will be appreciated that the locking between the
flanges 116, 126 causes the inner tube 110 and the outer cannula
120 to move axially together while both are rotating.
[0043] The spring loaded mechanism has another component thereof in
that it generally includes a pin and groove arrangement to control
the specific movements of the inner tube 110 as it is fired and
advanced away from the handle body 410 upon actuation of the spring
loaded mechanism. For example, the end 114 of the inner tube 110
has a flange member 113 which can be an annular flange or can be
less than an annular flange. The end 114 (flange 113 thereof) thus
has an opening formed thereat to permit the stylet 310 to be
received and removed therethrough.
[0044] It will be appreciated that the inner tube 110 should be
able to rotate within the flange 113 and therefore, it is preferred
that the flange 113 be connected to the inner tube 110 in a
non-movable manner so as to permit the inner tube 110 to rotate
when it axially advances as will be described hereinafter. For
example and as shown in FIG. 1, first and second locator members
177, 179 are disposed around the flange 113 so as to locate the
flange 113 and limit the movement thereof. More specifically, the
first locator member 177 is in the form of a distal flange (e.g.,
ring shaped) and the second locator member 179 (e.g., ring shaped)
is in the form of a proximal flange. These flanges 177, 179
prevents flange 113 from translating along an axial (longitudinal)
direction relative to the inner tube 110 but allows the inner tube
110 to freely rotate within the flange 113.
[0045] A second pivotable lever 170 is provided and is pivotally
connected to the flange 113 formed at the end of the inner tube
110. The lever 170 is preferably pivotally connected to the flange
113 at a first end 172 and has a claw or lip 174 formed at an
opposing second end 176. The illustrated claw 174 is a protrusion
that is generally perpendicular to the elongated body portion of
the lever 170. The lever 170 includes an opening 173 formed
therethrough to receive a pin or the like 180. In one aspect of the
illustrated spring loaded mechanism, the opening 173 is a slot that
is formed at an angle within the lever body and more specifically,
the slot 173 is angled upward in a direction toward the claw 174.
In the retracted, locked position of the spring loaded mechanism,
the pin 180 is disposed within the slot 173 near or at the end that
is closest to the claw 174 and after activation of the first lever
mechanism (actuator device 150), the pin 180 rides within the slot
173 toward the opposite end thereof causing the disengagement of
the second pivotable lever 170 as will be described in greater
detail hereinafter.
[0046] The illustrated pin and groove mechanism includes a second
biasing element 190 that is disposed between the flange 113 or
locator member 177 and a movable member 200 that is disposed around
the inner tube 110. The member 200 is free to slidably travel along
the inner tube 110 when it is unlocked from the claw 174 of the
lever 170. The member 200 thus has an opening extending
therethrough that accommodates the inner tube 110 and has a first
face that faces and is in contact with the second biasing element
190 and a second face that faces the alignment sleeve 160. In one
exemplary embodiment, the member 200 is generally in the form of a
ring shaped member. The member 200 has a surface that can be
engaged by the claw 174 so as to keep the second lever mechanism in
a locked position. In the locked position, the second biasing
element 190 is in a compressed state (storing energy) between the
first face and the distal locator member 177 that is adjacent the
flange 113.
[0047] According to the illustrated embodiment, the pin and groove
mechanism associated with the second pivotable lever 170 is formed
of a pin 210 and the inner tube 110 has one or more complementary
profiled grooves 115 formed therein. In the illustrated embodiment,
each groove 115 can have a first generally linear portion and a
second portion that is generally helical in nature.
[0048] The pin 210 is contained within the handle body 410 such
that it has two different stages of movement in that the pin 210 is
initially permitted to rotate with the inner tube 110 and then in a
second stage, the pin 210 moves forward in a single plane. More
specifically, the pin 210 is directly coupled to the member 200 by
any number of means such that movement of the inner tube 110 is
directly translated to movement of the member 200 and the pin 210.
For example, the pin 210 can be integrally formed with the member
200 so that it extends across a diameter thereof or the pin 210 can
be securely attached to the member 200 using any number of means.
For example, a pair of fastening members 211 can be formed as part
of the member 200 at locations about 180 degrees apart from one
another. Each member 211 can be generally in the form of a bridge
that has a space formed therethrough to receive the pin 210 so as
to securely attach the pin 210 to the member 200. Any other means
can be used to attach the two together.
[0049] Initially in the first stage of movement, the pin 210
travels within the groove 115 as it rotates along with the inner
tube 110. In other words, as the inner tube 110 rotates, the member
200 and the pin 210 also rotate and then, in the second stage, the
pin 210 moves forward in a single plane as it is advanced within
the one or more grooves 115. In other words, the pin 210 does not
have an up and down movement as it advances but rather it remains
substantially within one plane. This type of movement by the pin
210 is created by disposing the ends of the pin 210 within
longitudinal channels 220 that are formed in the handle body 410 on
opposite sides of the inner tube 110. The channels 220 are aligned
with one another so that they lie within one plane that also
contains the pin 210 during its travel in the second stage. One end
of the channel 220 is open so as to be able to receive the pin
210.
[0050] As will be appreciated, the inner tube 110 rotates as the
inner tube 110 and the outer cannula 120 are projected forward
while, the alignment sleeve 160 keeps these two members aligned
with one another. However, the pin 210 traverses the inner tube 110
perpendicular to the axial dimension. Therefore, the pin 210 should
be able to rotate with the inner tube 110 until it engages the
channels 220 only after the inner tube 110 has been projected
forward. In the present embodiment, the pin 210 does not engage the
channels 220 prior to the activation of the biasing element but
engages them once the inner tube 110 and the outer cannula 120 have
been projected forward. Since the inner tube 110 and the outer
cannula 120 rotate a defined number of degrees, the channels 220
can be placed in a position to accept the pin 210 once the rotation
is complete.
[0051] By directing the ends of the pin 210 into and along the
channels 220, the channels 220 act as guide tracks in that they
restrict and control the motion of the pin 210 after the unlocking
of the second lever mechanism 170 and after the pin 210 has
completed its rotation with the inner tube 110. The pin 210 is thus
limited to traveling within one plane since as it travels in the
second stage, it is restricted to traveling within the linear
channels 220.
[0052] It will be appreciated that since the stylet 310 does not
rotate, the stylet 310 has to accommodate the pin 210. In one
embodiment, the stylet 310 remains in the location shown in FIG. 1;
however, the pin 210 does not extend completely across the inner
tube through the stylet 310 but instead the pin 210 only enters the
groove 115 of the inner tube 110 a sufficient degree to rotatably
couple the two together while permitting the stylet 310 to remain
in a non-rotational state. In other embodiment, the stylet 310 is
moved more distally forward in the handle body 410 such that pin
210 can extend completely through the inner tube 110 without any
interference with the stylet 310. In other words, the stylet 310 is
positioned more distal than the pin slots 220 to allow the pin 210
to rotate with the inner tube 110 as it is advancing axially
forward.
[0053] Since the pin 210 may not exactly line-up with the channels
220 once the rotation of the inner tube 110 and the outer cannula
120 is complete, the proximal ends of the channels 220 where they
accept the pin 210 can be made wider then at the more distal ends
of the channels 220 where the pin 210 stops its forward motion.
Once, the pin 210 lies within the channels 220, the pin and groove
mechanism can be activated (second lever mechanism 170).
[0054] It will be appreciated that after the first stage of snare
activation in which the outer cannula 120 is advanced and rotated,
along with the inner tube 110, the second stage of the activation
of the snare preferably occurs once the flange 126 of the outer
cannula 120 has cleared the groove 165 and no longer can influence
rotation of the alignment sleeve 160. However, it will be
appreciated that even when the flange 126 is outside of the sleeve
160, it is still directly attached to the inner tube 110 via the
locking lips. In the second stage, the inner tube 110 is rotated,
as it remains axially steadfast, due to the activation of the
second biasing mechanism and release of stored energy in the second
bias element 190. Thus, one will appreciate that preferably at any
one point in time, the alignment sleeve is only under the influence
and is rotated by either the outer cannula 120 or the inner tube
110. More specifically, in the first stage, the outer cannula 120
causes the alignment sleeve and in the second stage when the flange
126 is free of the alignment sleeve, the release of energy stored
in spring 190 causes rotation of the inner tube 110 which is
translated into rotational of the alignment sleeve. Even though the
inner tube 110 is connected to the outer cannula 120, the locking
lips permit the inner tube 110 to rotate relative to the outer
cannula in the second stage, while the outer cannula 120 does not
have to rotate.
[0055] The operation of the device 100 will now be described. In
the retracted position, the actuator device 150 and the second
pivotable lever 170 are in the locked positions, whereby both the
first biasing element 130 and the second biasing element 190 are in
compressed states such that they store energy. To actuate the
device 100, the user presses, slides or otherwise manipulates the
button 152 causing the links 154, 156 to pivot and the claw 159
disengages from the flange 121 of the outer sleeve 119. As soon as
the claw 159 disengages, the first biasing element 130 releases its
energy by applying a biasing force against the flange 121, which in
turn causes the axial (longitudinal) movement of the outer cannula
120. As previously mentioned, the distance that these two elements
can axially travel is defined as distance x as illustrated in FIG.
1, namely the distance from the flange 121 to the handle body
410.
[0056] The first biasing element 130 is preferably a strong coil
spring since this biasing element needs to generate a sufficient
force that drives the inner and outer tubes 110, 120 into the
tissue so as to shear the soft tissue to permit it to be collected
as a result of the action of the snare 300.
[0057] The forward axial motion of the outer sleeve 119 is
influenced by the pin and groove arrangement in that the groove 123
formed in the outer sleeve 119 and the pin 127 cause the outer
sleeve 119 to rotate as it is projected forward. Since the outer
sleeve 119 is directly connected to the outer cannula 120, the
rotation and forward movement of the outer sleeve 119 is imparted
to the outer cannula 120.
[0058] As previously mentioned, the outer cannula 120 and inner
tube 110 are coupled to one another at their respective flanges
116, 126 by means of the first and second locking lips 127, 141,
respectively. Since the outer cannula 120 and inner tube 110 are
attached to one another, the rotation of the outer cannula 120 is
translated to rotation of the inner tube 110. The alignment sleeve
160 permits the inner tube 110 and the outer cannula 120 to not
only continue their forward projection but also it permits these
members to rotate uniformly. The tabs 117, 128 of the flanges 116,
126 move axially in the grooves 165 formed in the alignment sleeve
160 until the flange 126 of the outer cannula 120 becomes
disengaged from the alignment sleeve. Once the flange 126 becomes
disengaged from the alignment sleeve 160 (the tabs 128 clear the
groove 165), the outer cannula 120 is free to rotate independent
from the inner tube 110, while the two members are still coupled to
one another by the first and second locking lips 127, 141.
[0059] As soon as the forward motion of the outer cannula 120/outer
sleeve 119 is complete and when the flange 126 of the outer cannula
120 becomes disengaged from the alignment sleeve 160 by sliding out
of the grooves 165 thereof, the pin 210 is positioned at the
entrance or slightly within the channels 220 and then the second
pivotable lever 170 is actuated or fired to cause further rotation
of the inner tube 110 to actuate the snare 300. In other words,
once the forward projection of the outer cannula 120 is complete
and the pin 210 is properly positioned relative to the channels
220, the second pivotable lever 170 fires because the second
pivotable lever 170 is connected to the inner tube 110 and
therefore it will move along with the inner tube 110 after the
actuator device 150 is activated. As the second pivotable lever 170
moves axially with the inner tube 110, the fixed pin 180 rides
within the slot 173 toward the opposite end of the slot 173.
Because the slot 173 is ramped or angled downward toward this
opposite end, the relative movement of the fixed pin 180 within the
slot 173 causes the second pivotable lever 170 to pivot upward
about the pivot point between the lever 170 and the flange 113. As
the lever 170 pivots upward, the claw 174 lifts up from its
engagement with the member 200, thereby releasing the member 200
from its locked position. As soon as the member 200 is disengaged
from the claw 174, the member 200 is free to move axially
(longitudinally) along the inner tube 110 and the second biasing
element 190 can release its energy. The second biasing element 190
applies a force against the member 200 in a direction toward the
outer cannula 120/alignment sleeve 160.
[0060] The pin 210 is placed adjacent and coupled to the member 200
such that when the second biasing element 190 applies a force
against the member 200, the force is also translated to the pin 210
causing the pin 210 to ride within the one or more grooves 115 that
are formed in the inner tube 110. Because the ends of the pin 210
are constrained within the longitudinal channels 220, the pin 210
can only be advanced within one plane when it is "fired" forward by
the biasing force of the second biasing element 190. Because the
pin 210 is constrained to one plane, its forward advancement is
translated into a rotational movement of the inner tube 110 due to
the presence of the profiled helical portion of the groove 115.
However, the inner tube 110 is not axially advanced as it rotates.
As will be appreciated, the pin 210 advances within the channels
220 but at the same time, the pin 210 advances within the groove
115 from the linear portion to the helical portion. The only way
that the pin 210 can advance within the groove 115 and still remain
within the channels 220 is if the inner tube 110 rotates to
accommodate such movement of the pin 210. The helical nature of the
groove causes such rotational movement of the inner tube 110.
[0061] It will be appreciated that the profile of the groove 115
can be varied and depending upon its precise characteristics, the
movement of the inner tube 110 is controlled. For example, if it
desired for the rotation of the inner tube 110 to be staged later
in time, the length of the linear portion can be increased and
therefore, the pin 210 does not enter into the helical portion as
quickly as before and therefore, the rotation of the inner tube 110
is delayed.
[0062] Since the free end of the snare is fixed to the outer
cannula 120, the result of the rotation of the inner tube 110 is
that the coil of the snare tightens so that the cross-sectional
area through the snare is approximately less than a third of the
area when in the open configuration. It is also contemplated that
any decrease, even a slight decrease, in the cross-sectional area
of the snare will cause pressure on the biopsy piece. Therefore,
the amount of rotation can be varied and there is no particular
amount that is necessary for the proper functioning of the present
invention.
[0063] With the tightening of the snare, there is a high
probability that the biopsy piece will remain in the needle as the
needle is removed. If the tightening of the snare does not
immediately cause the biopsy piece to be cut, it will be
significantly squeezed and/or notched, such that rearward motion of
the needle, which causes rearward pressure on any biopsy piece
proximal of the snare, will cause material proximal of the snare to
detach from material that is distal of the snare.
[0064] The pin 210 advances forward until either (1) the pin 210
reaches the ends of the channels 220; (2) the pin 210 reaches the
end of the helical portion; or (3) the pin 210 contacts the sleeve
160.
[0065] In the embodiment shown in FIG. 1, the flange 113 does not
move axially relative to the inner tube 110 although it does move
axially relative to the handle body 410. The flange members 177,
179 permit the inner tube 110 to rotate within the flange 113 and
in addition, the flange 113 does not rotate relative to the handle
body 410 since the flange 113 is constrained by the interaction of
the lever 170 and the pin 180.
[0066] The present construction can therefore be thought of as a
two stage mechanism in which the first stage is the firing of the
actuator device 150 (first release of stored energy) to cause the
sudden longitudinal advancement of the inner and outer tubes 110,
120 away from the handle body 410. This in turn causes the second
pivotable lever 170 to disengage and there is a second firing of
the second biasing element 190 which leads to the second stage
where the inner tube 110 is rotated.
[0067] The operation of the snare 300 including the collection and
removal of the soft tissue sample is preferably along the same
lines as that which is disclosed in the patents disclosed
hereinbefore.
[0068] The device can be reset using a sleeve and pin assembly as
described previously. However, it is possible that the outer
cannula flange 126 may not line up completely with the alignment
sleeve 160 as the inner tube 110 and outer cannula 120 move
backward into position and therefore, an additional mechanism might
be required to compensate for this possibility. One such mechanism
can include increasing the dimensions of the complementary portion
(channel or groove 165) that accepts the flange 126 to allow the
flange 126 to "find" its way into the grooves 165 and reset
properly.
[0069] One will appreciate that the speed of needle transit into a
specimen with significant internal structure does not have to be
excessive since the internal structure provides stability and
supports the shearing of the specimen by the needle. However,
needle transit into tissue must be excessive for tissues with
moderate or minimal internal structure in order that an appropriate
shearing and tissue cutting force is developed. Moreover, not only
shearing but transit of the specimen into the needle is facilitated
by specimens with significant internal structure. Tissue with
minimal internal structure does not support transit of the specimen
into the needle as well and requires the needle to "move over" the
specimen in a rapid fashion to facilitate specimen acquisition. The
present design is one in which the needle, with stylet in place,
can be brought to a certain position and the coring needle can then
be rapidly advanced beyond the fixed position of the stylet.
Accordingly, the present spring loaded mechanism projects the
needle over the stylet in a matter of microseconds.
[0070] In sum, the pin and groove mechanism for rotating the snare
coil has been developed to eliminate the need for an operator to
rotate a lever to actuate the snare coil in applications where it
is desirable to have a hand-held device that is spring-loaded and
fired by pressing an activating button. Further, it coordinates the
rapid axial projection of a needle with the requirement for a
rotating movement to actuate the snare coil. The pin and groove
mechanism can achieve these requirements through a number of
different embodiments. In these embodiments, the pin moves along
the groove and this can be achieved by either translating a sleeve
axially relative to a pin that does not move axially or vice versa
translating the pin (can be attached to a tubular structure)
relative to a grooved sleeve that does not move in an axial
position. In each of these configurations, one component (either
the sleeve or pin) does not rotate, while the other component does
rotate. The component that rotates is connected to the internal
snare coil tubular member. In one embodiment, if the pin is fixed
and does not rotate, axial movement of the sleeve causes the sleeve
and any tube attached thereto (e.g., inner tube attached to snare
coil) to rotate. In the second embodiment, if the sleeve does not
rotate, that is, it is fixed in a nonrotatable position when it is
translated along an axial direction, the pin will rotate and any
tubular member connected to the pin, such as the internal snare
coil cannula, will rotate as well.
[0071] It will be appreciated that the above described rotating
needle construction is not limited to a needle having a snare coil
design but rather a rotating needle construction can be provided
for a simple coring needle. More specifically, a simple coring
needle can incorporate the above rotational aspects by having a
cannula with a grooved sleeve and pin mechanism to cause the
cutting cannula to rotate as it is projected forward but does not
include the inner tube with a snare coil coupled at one end
thereof. The pin and groove mechanism thus can be used as a means
for causing rotation of one cannula to another to cause this
cutting (coring) cannula to rotate, thereby cutting the tissue for
collection as opposed to actuating a snare coil (which is not
present in this embodiment).
[0072] In an embodiment that incorporates the above first and
second stages but does not include a snare, a simple rotating
needle is provided and there is only a boring tube or cannula and
sleeve 119 which is coupled thereto and the first biasing element
130. In this embodiment, there is no snare and the cutting action
is derived from the rotation of the cannula 120 which is caused by
the pin and groove mechanism 127, 123 that has been previously
described. Thus, a simple rotating needle assembly is illustrated
which is actuated using device 150.
[0073] It will also be understood that both the pin and groove
mechanisms that are associated with the sleeve 119 in both of these
embodiments can be modified so that the sleeve 119 has at least one
pin formed as a part thereof and a groove is formed as part of the
handle body and therefore, the rotating action is generated by the
pin riding within the groove formed as part of the handle body.
[0074] FIG. 13 illustrates yet another aspect of the present
invention in which a three cannula biopsy needle 500 is provided.
The needle 500 includes the inner tube 110, the outer cannula 120
and a retractable cannula 510. The construction of the inner tube
110 and outer cannula 120 and their operative cooperation with the
snare 300 is similar to that disclosed in any of the above
incorporated U.S. patents. The outer cannula 120 includes a cutting
portion 502 formed at a distal end thereof and also includes a
shoulder 504 that is defined by the cutting portion 502 and an
elongated body of the outer cannula 120.
[0075] Each of the inner tube 110 and the outer cannula 120
includes a cut out or window formed therein. More specifically, the
inner tube 110 includes a window 512 formed near but spaced from
the distal end thereof. The window 512 is formed by removing a
predetermined amount of the body of the inner tube 110 and in one
embodiment, the window 512 is formed by removing between about 50%
to 85% of the circumference of the body of the inner tube 110. For
example, the window 512 can extend about 75% of the circumference
of the inner tube 110. The distalmost section of the inner tube 110
is formed next to the window 512 and extends to the snare 300.
Similarly, the outer tube 120 includes a cut out or window 514 that
is formed near but spaced from the distal end thereof. The window
514 is formed by removing between about 50% and 85% of the
circumference of the body of the outer cannula 120, e.g., removing
about 75%. Preferably, the circumferential characteristics of the
windows 512, 514 are complementary so that the two windows 512, 514
are in registration with respect to one another at select
times.
[0076] More specifically, after the snare 300 has been actuated as
disclosed in the above incorporated patents or in another manner
and the inner tube 110 completes its rotation with respect to the
outer cannula 120, the windows 512, 514 are preferably in complete
registration with one another so that an individual outside of the
outer cannula 120 can reach through the aligned windows 512, 514
and into the interior of the inner tube 100 to retrieve the
collected specimen. Preferably, the windows 512, 514 are in
complete registration with one another; however, the windows 512,
514 do not necessarily have to be perfectly aligned for the user to
gain sufficient access therethrough to retrieve the collected
specimen.
[0077] The retractable cannula 510 is complementary in size and
shape to the other two cannulas so that the retractable cannula 510
slidably extends over the outer cannula 120. The retractable
cannula 510 has a distal end 516 that abuts or nearly abuts the
shoulder 504. A portion 518 of the outer cannula 120 adjacent the
shoulder 504 serves as a platform or leading ledge so that the
distal end of the retractable cannula 510 sits on the platform 518
when the retractable cannula 510 is in the fully extended position,
whereby the windows 512, 514 are closed.
[0078] The retractable cannula 510 preferably extends into a handle
body (not shown) and is operatively coupled thereto using
conventional means so that it can be easily retracted along the
outer cannula 120. For example, a biasing mechanism can be used to
apply a biasing force against the retractable cannula 120 so that
it remains in the fully extended position during normal operating
conditions. In order to retract the retractable cannula 510 and
expose the windows 512, 514, the user simply applies a force
against the cannula 510 that overcomes the biasing force resulting
in the retraction of the cannula 510 toward the handle body until
the windows 512, 514 are exposed. It will be appreciated that the
retractable cannula 510 can be locked in a retracted position using
conventional releasable locking mechanisms so that the cannula 510
can remain locked out of the way of the windows 512, 514. For
example, a releasable biased tab/detent type arrangement can be
used.
[0079] It will be appreciated that in the present illustrated
embodiment, the needle 500 is constructed of three cannulas each
successively placed within the other. The middle cannula is the
outer cannula 120 and it is thicker than the others since it
provides for the majority of the strength and stability of the
needle assembly. The snare 300 is attached to the innermost tube
(inner tube 110) at its distal end. The inner tube 110 has the
smallest thickness and as with the outer cannula 120, the cut away
portion leaves the inner tube 110 with a cradle like
appearance.
[0080] Since this embodiment includes a needle incorporating three
cannulas, it is important to minimize the wall thickness of one of
the cannulas and possibly two of them to minimize the diameter of
the whole needle 500. It is possible that the inner tube 110 can be
made of a durable thin plastic material with the snare 300 molded
or lasered into the end of the inner tube 110. The retractable
cannula 510 can be made of a thin medical grade stainless steel and
the outer cannula 120 can be constructed of a thicker medical grade
stainless steel. As the whole needle 500 represents a composite of
three cannulas, the overall strength of the needle 500 with respect
to its resistance towards bending is substantial.
[0081] In another embodiment, the most distal portion of the
innermost tube 110 beyond the snare 300 can have a type of tab lock
which could integrate with the needle tip of the outer cannula 120
to allow for a secure connection and rapid manufacturing.
[0082] Thus, in the embodiment shown in FIG. 13, the needle 500
incorporates a retracting part to facilitate recovery of a specimen
that is contained within the inner tube 110.
[0083] It will be appreciated that the above described retractable
needle construction is not limited to a needle having a snare coil
design but rather a retractable needle construction can be provided
for a simple coring needle. More specifically, a simple coring
needle can be a two cannula needle with the inner cannula having a
window cradle (a cut out as described above) and the outer cannula
can operate as the retractable cannula. This embodiment does not
incorporate a third snare coil cannula. It will also be appreciated
that in this embodiment, the inner cannula can be designed to
rotate as described above due to a pin and groove construction,
while it still remains a coring needle without the provision of a
snare coil.
[0084] In yet another embodiment, the present biasing mechanisms
can be incorporated into a non-snarecoil rotating needle. In other
words, this type of needle has a simple boring tube that has a
biasing mechanism, such as the first biasing mechanism of FIG. 1,
that causes the rapid axial advancement of the boring tube due to
the release of energy that is stored in the first biasing element
against the flange of the boring tube. The needle also has a
rotating mechanism, such as the pin and groove arrangement of FIG.
1, that causes the rotation of the boring tube either concurrently
with the axial advancement of the boring tube or after the boring
tube has reached its end of axial travel. In this embodiment, there
is no inner tube and no automatic active capture mechanism that
results in actuation of a snarecoil since there is no snarecoil. As
with the other previous embodiments, the rotating mechanism of the
boring tube preferably includes one component, such as a pin or
helical slot, that moves axially and another component, such as a
helical slot or pin, that is axially steadfast. Either pin or the
helical slot or even a helical ridge as described above can be
associated with the boring tube, while the other complementary
component is formed as part of the housing of the handle
assembly.
[0085] In yet another embodiment, shown in FIG. 12, a needle 600,
such as the ones disclosed hereinbefore, includes an outer cannula
610 and an inner tube 620 that has or is connected to a snare 630
at a distal end thereof as previously described above and in the
aforementioned patents. The outer cannula 610 includes a slot 612
that is formed therethrough to provide access into the interior of
the outer cannula 610. For example, the slot 612 can have any
number of different shapes and sizes so long as the slot 612
provides sufficient access into the interior of the outer cannula
610. The illustrated slot 612 is generally oblong shaped and is
formed near the distal end of the outer cannula 610.
[0086] The inner tube 620 has a complementary slot 622 formed
therein which is selectively axially aligned with slot 612 when the
inner tube 622 is rotated within the outer cannula 610 to a
position where the slots 612 and 622 at least partially overlap one
another. The slot 622 extends completely through the inner tube 620
so as to permit the user to access the interior of the inner tube
620.
[0087] When the slots 612, 622 are aligned, a window is opened and
permits the user to access the interior of the inner tube 620 from
outside the outer cannula 610 by inserting an instrument through
the side window into the interior of the inner tube 620 to access
the specimen so that it can be removed through the window.
[0088] The inner tube 620 and the outer cannula 610 are arranged
relative to the operable mechanisms of the needle such that when
the inner tube 620 and outer cannula 610 are rapidly advanced
forward the snarecoil 630 is actuated, the window defined by
aligned slots 612, 622 remains closed. After the cutting/shearing
action occurs, the snarecoil 630 is closed with the specimen being
captured within the inner tube 620, the user then simply rotates
the inner tube 620 so as to cause the inner slot 622 to become at
least partially aligned with the outer slot 612, thereby opening
the window and permitting easy removal of the specimen.
[0089] In addition, it will be appreciated that the window feature
shown in FIG. 12 and the vacuum feature described below can be
combined with any of the needle embodiments disclosed herein. For
example, the window feature can be used in both snarecoil type
needles and non-snarecoil type needles and can be used in needles
that incorporate one or more of the mechanisms that either drive
the needle axially forward or cause rotation of a part of the
needle. Similarly, the window feature can be combined with the
vacuum feature or the needle can include only one of these features
and the vacuum feature similarly can be used in any of the above
embodiments, including both snarecoil type needles and
non-snarecoil type needles.
[0090] As previously mentioned, soft tissue specimens may not enter
a needle as readily as specimens with more substantial internal
structure because of issues of inadequate shearing/cutting and
compromised specimen transit into the needle. One method of causing
the specimens to more readily enter the needle is to create
negative pressure (e.g., a vacuum condition) within the inner tube
where the specimen is collected. Unfortunately, the existing needle
constructions that have means for generating a negative pressure
within the inner tube are very complex. For example, existing
needle products include a cumbersome external vacuum device for
generating the negative pressure.
[0091] Another way to generate a negative pressure internal to the
needle is a means that takes advantage of the concept that when the
needle is "thrown" forward over the stylet, the stylet is moving
backward relative to the needle. As a result, the incorporation of
a seal, such as a rubber O-ring or the like, between the stylet and
the inner tube can generate a small but significant vacuum internal
to the distal portion of the needle facilitating specimen transit
into the needle. The vacuum is thus generated when the needle is
"thrown" over the stylet and is cutting the tissue. For example,
the needle can be "thrown" as a result of actuation of one of the
aforementioned mechanisms.
[0092] The above feature of creating a negative pressure within the
needle as it is fired can be the basis for a new biopsy technology.
In one embodiment, a full core soft tissue needle projected forward
and fired over a stylet that incorporates an air seal of some sort
can generate enough internal negative pressure to not require the
inclusion of a snarecoil in the needle to facilitate specimen
recovery. Thus, in one embodiment, the snarecoil is removed and
specimen recovery results from the application of a vacuum to the
site.
[0093] In FIG. 2, the needle 100 is provided and includes inner
tube 110 with the flange or the like 116 formed as a part thereof;
the outer cannula 120 disposed around the inner tube 110; and the
stylet 310. The stylet 310 has an outside diameter that is less
than the diameter of the bore formed through the outer cannula 120
and therefore, there is a space or gap that is formed therebetween.
In one embodiment, the flange 116 is an annular ring shapes member
that extends outwardly from the inner tube 110. The outer cannula
120 also includes the flange or the like 126 that extends
therearound.
[0094] A first seal element is disposed between the outer cannula
and the inner tube 110. Any number of seal elements can be used,
including but not limited to a rubber washer like member, an
O-ring, a lubricant, or other sealant. A second seal element is
disposed between the stylet 310 and the inner tube 110. As with the
other embodiments, the second seal element can be in the form of a
rubber ring, such an O-ring or it can be some other type of seal
member or material. This second seal element that is disposed
between the stylet 310 and the inner tube 110 acts as a
positionably piston that generates the internal negative pressure
in the needle, e.g., within the inner needle, to help draw the
specimen by negative pressure into the inner tube 110. In other
words, seal element allows the inner tube 110 and outer cannula 120
to act as a composite tube which the stylet 310 works against to
generate the vacuum.
[0095] According to this aspect of the present invention, the soft
tissue needle incorporates inner tube and outer cannula which are
fired or rapidly projected forward over the stylet that has some
material (second seal) disposed between the stylet and the inner
tube that acts as an air seal. While the seal can be in the form of
an O-ring, it can also be in the formed of some type of medically
compatible polymer that sits between the inner tube and the stylet
and it does not result in significant friction and seals the
forward space from atmospheric pressure. This concept can also be
applied to needles having a cumbersome external vacuum source, such
as a Mammotome design from Ethicon Industries. In this type of
embodiment, the outer cannula is not thrown forward rapidly but
moves slowly as the inner circulating cutting blade cores out a
specimen. In such a design, a shaft with an air sealing component
remains steadfast as the outer needle is slowly projected forward
thereby producing as distal internal vacuum and not requiring the
external vacuum device to generate the force to facilitate specimen
transit and retention in the needle.
[0096] It will be appreciated that the above described vacuum
generating means can be employed in both a snarecoil design and a
standard biopsy needle that does not include a snarecoil.
[0097] In yet another embodiment, a non-snarecoil rotating needle
is provided and shares similar features as the needle of FIG. 1. In
this embodiment, the needle has a simple boring tube that has the
first stage rotation described above (e.g., cause by rotation of
the sleeve 119) but does not include an inner tube and the second
stage rotation, and thus the alignment sleeve 160 is eliminated
also. In this embodiment, the boring tube advances axially due to
actuation of mechanism 150 and as it axially advances, the
interaction between elements 123, 127 causes rotation of the boring
tube.
[0098] In another embodiment, a torque generating mechanism is
provided and includes the second pivotable lever 170 and the second
biasing element 190; however, the linear channels 220 and the ring
shaped member 200 are eliminated. In this embodiment, an inner tube
is provided and is similar to tube 110 with the exception that the
helical groove is eliminated and replaced with one or more
projections (bosses) that extend outwardly from an outer surface of
the inner tube, preferably at a right angle thereto. If two
projections are provided, they are preferably orientated 180
degrees apart. In this embodiment, the mechanism includes an
axially driven helical sleeve that is disposed about the inner tube
and includes one or more helical grooves or slots formed therein,
similar to grooves 115 in FIG. 1. If there are two projections,
then there are two slots. The sleeve also includes one or more,
preferably two, guide fins or projections that ride within guide
channels formed in the inner housing body 410 so as to prevent
rotation of the sleeve as the sleeve travels axially within the
housing.
[0099] The sleeve is contained in the housing body 410 and is
permitted a degree of longitudinal axial travel therein. The sleeve
includes a proximal end that has an opening or slot formed thereat
with a distal end. The helical slot has an initial linear portion
into which the projection is disposed and will travel in as the
inner tube moves axially in the first stage due to the firing of
the first biasing element 130 and movement of the outer tube 120
similar to FIG. 1. The slot of the sleeve is initially engaged and
locked by the claw 174 of lever 170. As in FIG. 1, after a
predetermined distance of axial travel, the lever 170 disengages
from the sleeve, thereby causing the second biasing element 190 to
release its energy against the flange to cause axial movement of
the sleeve about the inner tube which does not move axially any
more since the first stage is completed. It will be appreciated
that once the sleeve is fired over the axially stationary inner
tube, the engagement between the projections and the helical slots
causes rotation of the inner tube and thereby causes activation of
the snare. Once again, this embodiment shows an automatic active
capture mechanism that is automatically fired after actuation of
the first stage (longitudinal firing of the inner tube and the
outer cannula 120) and at a predetermined time relative to the
completion of the first stage.
[0100] After firing, the degree of axial travel of the sleeve can
be restricted by a stop or the like, such as an object formed as
part of the housing 410 and in any event, the travel of the sleeve
will be limited by the presence of the flange 116. Once again, the
guide channels prevent rotation of the axially advancing
sleeve.
[0101] While exemplary drawings and specific embodiments of the
present invention have been described and illustrated, it is to be
understood that the scope of the present invention is not to be
limited to the particular embodiments discussed. Thus, the
embodiments shall be regarded as illustrative rather than
restrictive, and it should be understood that variations may be
made in those embodiments by workers skilled in the art without
departing from the scope of the present invention as set forth in
the claims that follow, and equivalents thereof. In addition, the
features of the different claims set forth below may be combined in
various ways in further accordance with the present invention.
* * * * *